The purpose of this project is to investigate the role of the central nervous system in behavior. In some experiments we examine the contribution of somatic factors in instrumental cardiovascular conditioning. Brain areas of special interest are the hippocampus, the caudate nucleus and the pyramidal tract; subjects are monkeys (Macaca mulatta). In other experiments we examine the age-related changes in pre- and post-synaptic portions of the nigrostriatal pathways using behavioral and biochemical analytical methods. The present topics of interest include possible alterations in: (a) developmet of post synaptic denervation hypersensitivity; (b) specificity and affinity of dopaminer receptor binding; (c) adenyl cyclase production; and (d) synaptic release mechanisms that might occur with age.